The present invention is generally related to washing machines and, more particularly, to a process and system for selectively controlling agitator motion patterns, and water level in the washing machine.
Use of electronic controllers in washing machines have allowed to provide agitator control techniques that in varying degrees have partially addressed some relatively narrow needs. For example, U.S. Pat. No. 4,779,431 purports that an agitator drive that produces sinusoidal agitator motion in a washing machine, as opposed to square wave type of motion, results in somewhat improved wash action.
U.S. Pat. Nos. 4,542,633 and 4,554,805 disclose an agitator drive system that uses a rotational angle detector. Both of such patents appear to be limited to providing a fixed agitator stroke angle at a fixed rate of strokes/min, independently of the type of load or articles to be cleansed.
None of the foregoing controllers allow the washing machine for selectively controlling the agitator motion pattern so that the agitator motion pattern, e.g., angle of travel of the agitator and/or strokes/min of the agitator can be selectively adjusted to reflect a desired agitator motion pattern based on the specific characteristics of the articles to be cleansed, such as the type of fabric of the articles, the level of dirtiness of such articles, etc. In addition, none of the foregoing controllers, allow for implementing agitator control techniques by measuring predetermined inertial characteristics of the agitator that allow for selectively adjusting the water level of the washing machine based on the true needs of a given washing or rinsing cycle. In View of the above, it would be desirable to provide a control system and techniques for selectively controlling the agitator motion pattern based on the characteristics of the articles or load to be cleansed, as indicated by the user. It would also be desirable to adapt the same techniques to adjust the water level of the washing machine so that inexpensively and reliably the user of the washing machine is able to conserve a valuable natural resource, i.e., water, while at the same time ensuring that no fabric damage occurs due to inappropriate load density in a given washing cycle.
Generally speaking, the present invention in one embodiment fulfills the foregoing needs by providing a process for controlling respective agitator motion patterns in a washing machine having a motor drive coupled to energize a motor that drives the agitator. The process allows for selecting a desired agitator motion pattern based on one or more pattern selection signals. The process further allows measuring one or more parameters indicative of the actual agitator motion pattern. A comparing step allows for comparing the actual agitator motion pattern against the desired agitator motion pattern, and an adjusting step allows for adjusting one or more control signals supplied to the motor drive for correcting deviations between the actual agitator motion pattern and the desired motion pattern.
The present invention in another embodiment further fulfills the foregoing needs by providing a control system for controlling respective agitator motion patterns in a washing machine having a motor drive coupled to energize a motor that drives the agitator. The system comprises a selecting module configured to select a desired agitator motion pattern based on one or more pattern selection signals. The system further comprises a measuring module configured to measure one or more parameters indicative of the actual agitator motion pattern and a comparing module configured to compare the actual agitator motion pattern against the desired agitator motion pattern. An adjusting module is configured to adjust one or more control signals supplied to the motor drive for correcting deviations between the actual agitator motion pattern and the desired motion pattern.
In yet another embodiment, the present invention fulfills the foregoing needs by providing a washing machine programmed for selectively controlling agitator motion patterns. The washing machine includes a motor that drives the agitator. The washing machine further includes a motor drive coupled to energize the motor, and a controller coupled to supply one or more control signals to the motor drive. The controller in turn comprises a selecting module configured to select a desired agitator motion pattern based on one or more pattern selection signals. The controller further comprises a measuring module configured to measure one or more parameters indicative of the actual agitator motion pattern, and a comparing module configured to compare the actual agitator motion pattern against the desired agitator motion pattern. An adjusting module is configured to adjust the one or more control signals supplied to the motor drive for correcting deviations between the actual agitator motion pattern and the desired motion pattern.